That vehicle is throttle body fuel injected, there is no choke or idle adjustments. You have other issues such as a large vacuum leak causing your idle problem.
No.
Idle Air Control Valve
No it does not.
You don't, it is done by the ECM (Engine Control Module).
It is built into the alternator. It is all 1 unit.
Could be in need of a tune up Could have a vacuum leak
Clean EGR valve, maybe stuck open with carbon
Yes
what is the wheel base for 1985 s10 blazer
http://ui.abimg.net/images/answers/598789/2282485/1988.S10.Blazer.Vac.jpg?1328637075a
The shaft inside the trans will have to be changed it is longer in a 2 wheel drive and the taIL SHAFT.
Need to know what year, engine size and if it has a carburetor or throttle body injection (TBI).